Nonskid device for crutches and the like



S. H. RICHARDS NONSKID DEVICE FOR GRUTCHES AND THE LIKE Sept. 14, 1948.

Filed Feb. 24, 1947 Patented Sept. 14, 1948 NONS KID DEVICE FOR CRUTCHESAND THE LIKE Sidney H. Richards, Portland, Maine Application February24, 1947, Serial No. 730,491

l 6 Claims.

Most canes and crutches are covered at the lower end with a tip ofrubber or similar material which will prevent the crutch or cane fromslipping on a dry surface and which will not scar a polished surface.When this type of tip is used on ice and snow, it is found to be veryslippery and dangerous. Devices have been designed for use on crutcheswhen being used on ice, but these are of such type that if used on apolished surface they may scar the surface.

One object of the present invention is to provide a non-skid devicewhich can be installed readily upon any pair of crutches or the like andwhich can be advanced to an operative position or retracted to aninoperative position. Another object is to provide a non-skid devicewhich will contact the floor evenlyeven though the crutch may meet thefloor at varying slight angles and alsoto provide a non-skid devicewhich will not collect ice and snow.

The present invention comprises non-skid gripping means with a sharpedge or edges, prongs or the like, held in position around the rubbertip of the. crutch by means of a helical spring. The spring allows thegripping means to tilt slightly so that the gripping means contacts thefloor evenly with maximum gripping effect. The helical spring isattached to the shank of the crutch by a lateral lug which is preferablyin the form of a pin passing between the coils of the spring and throughthe crutch. By rotating the spring the gripping means may be retractedfrom an operative position below the end of the shank to an inoperativeposition above the end of the shank. The gripping means is substantiallylarger than the tip of the shank so that snow and ice may pass clear ofthe gripping means.

For the purpose of illustration a typical embodiment of the invention isshown in the accompanying drawings in which Fig. 1 is a side view of thenon-skid device retracted to inoperative position;

Fig. 2 is a side view of the non-skid device advanced in operativeposition;

Fig. 3 is an isometric view of a modified nonskid device;

Fig. 4 is a section on line 44 of Fig. 1;

Fig. 5 is a bottom plan; and

Fig. 6 is a section on line 6-6 of Fig. 1.

The particular embodiment of the invention chosen for the purpose ofillustration is for use on a crutch of well-known type havin a shank Ion the end of which is a tip 2 of rubber or similar material whichcontacts the floor. The

non-skid device may comprise a metal ring 3 with a sharp lower edge orany irregular or circular shape with a sharp edge, teeth, prongs, or thelike, capable of being sharpened, which are suitable to dig into the iceand snow. The ring 3 is large enough so that it will passover therubbertip 2 on the shank I with suificient space between the rubber tip 2 andthe ring 3 so that ice or snow may pass through. The ring 3 is connectedto a smaller ring 4 by upright members Ewhich slant upwardly andinwardly. There'is sufiicient space between the aforesaid up-. rightmembers 5 toallowice and snow to pass Jbetween them and clear thenon-skid device. .On top of said ring 4 is attached a helical spring Bof the same size approximately as the ring 4. The helical spring 6 mayend atthe top with a slight upward curve-Ill at the upper end of thecoil as shown in Figs. 1 and 2, or it may be capped with another ring Ias shown in Fig. 3. The ring 4 is slightly larger than the shank I ofthe crutch over which it is placed when installed so that the ring 4 maytilt slightly. Crutches with a shank of rectangular or larger size maybe rounded to receive the ring 4.

Referring to Fig. 6 a metal tube 9 is placed on the shank I to provide asmooth bearing surface for the ring 4 and the spring 6. Because the ring4 is larger than the shank, the ring 4 may tilt slightly,against theaction of the helical spring 6, with the result that the lower edge ofthe ring 3 contacts the floor evenly even when the shank of the crutchmakes a slight angle with the floor. The metal tube 9 provides a strongbearing surface for the ring 4 when it tilts slightly and prevents thetendency of the ring 4 to dig into the shank I.

The helical spring 6 is held on the shank I by means of a lug 8 whichpasses between the coils of the spring 6 and through the shank I. In theembodiment which comprises a spring ending with a slight upward curveIll the lug 8 may be installed first through the shank and then the coilspring may be threaded onto the lug 8. In the embodiment with the upperring I the spring must be placed first on the shank I and the lug 8 thenplaced through the shank I.

The lug 8 may be thicker than the space between the coils of the spring,thereby holding the spring 6 from rotating, or the lug may be placed soit does not exactly coincide with the spaces between the coils of thespring causing the spring to bear on one side of the lug at all times,thus holding the non-skid device from getting out of position. By merelyrotating the coil 6 the nonskid device can be positioned above therubber tip 2 or it can be positioned at various levels below the rubbertip 2 so that the portion of the weight carried by the non-skid devicemay be varied in order to get the most satisfactory penetration of thering 3 into the ice and snow.

When the ring 3 is advanced to operative position below the rubber tip 2on the end of the shank l, the ring contacts the ground before therubber tip and the weight of the user causes the sharp edge or teeth onthe ring to dig into the ice and snow. As the shank l is forced down bthe weight of the user it carries with it the lug 8, thereby compressingthe helical spring 6. The rubber tip 2 may or may not contact theground, but if it does it carries a portion of the weight. 3 below therubber tip the portion of weight carried by the ring can be adjusted toattain a suitable gripping action.

It should be understood that the present disclosure is for the purposeof illustration only and that this invention includes all modificationsand equivalents which fall within the scope of the ap e d d ai s- I;claim:

1. For use on the lower end of the shank of a crutch having a laterallug, a non-skid device QQmprising a helical spring fitting over saidend, and non-skid gripping means mounted on the bottom of the springaround said end, the spring being threaded on said lug so that thegripping means may be advanced beyond said end by rotation of the coilin one direction and may be retracted into inoperative position aroundthe end by rotation in the opposite direction.

2. For use on the lower end of the shank of a crutch having a laterallug, a non-skid device comprising a helical spring fitting over saidend, and a circular ring with a sharp lower edge mounted on the bottomof thespring around said end, the spring being threaded on said lug sothat the gripping means may be advanced beyond said end by rotation ofthe coil' in one direction and may be retracted into inoperativeposition around the end by rotation in the opposite direction.

3; For use on the lower end of the shank of a crutch having a laterallug, a non-s kid device comprising a helical spring fitting over saidend, and a circiilar ring substantially larger than said endwith a sharplower edge mounted on the bottom of the spring around said end byupright By adjusting the distance of the ring a 4 members with spacesbetween, the spring being threaded on said lug so that the grippingmeans may be advanced beyond said end b rotation of the coil in onedirection and may be retracted into inoperative position around the endby rotation in the opposite direction.

4. For use on the lower end of the shank of a crutch or the like, anon-skid device comprising a helical spring fitting over said end,non-skid gripping means mounted on the bottom of the spring around saidend, and a lug projecting laterall from said end between the coils ofthe spring, whereby the gripping means may be advanced beyond said endby rotation of the coil in one direction and may be retracted intoinoperat-iveposition around the end by rotation in the oppositedirection.

5. For use on the lower end of the shank of a crutch or the like, anon-skid device comprising a helical spring fitting over said end, acircular ring with a sharp lower edge mounted on thebottom of the springaround'said end, and a lugproject ing'laterally, from said end betweenthe 'coils, of the spring, whereby: the gripping means may beadvancedbeyond said end by rotation of; thecoil in one direction and maybe retracted into inoperative position around the end by rotation in theopposite direction. 7

6. For use on the lower end of the shank of a crutch or the like, anon-skid device comprising a helical springfitting over said end, acircular ring with a sharp lower edge mounted on the bottom of.thespring around said end by uprightmembers with spaces between, and alug projecting laterally from saidend between the coils of the springs,whereby the gripping means'may. be ad? vanced beyond said end byrotation of the coil in one direction and may be retracted intoinoperative position around the endby rotation in'the oppositedirection.

SIDNEY H.v RICHARDS.

REFERENCE-S CIT-ED The following references are of record in the file ofthis patent:-

UNITED' STATES PATENTS Number Name Date 970,497 Harding Sept. 20 19101,132,119 Restorfi et al Mar.-16, 1915. 1,717,314 Frantz June 11', 1929'

